What constitutes a complete front end build system?

front-end-build.txt

 A good front end build system can consist of various different things. 
 However, I think it can be agreed upon that at it’s core, there are important core features. 

1. Run time
2. Tree shaking
3. Hot reloading
4. Minification 
5. Compilation Time 
6. Introduction of new module to core build system
7. Package management
8. Ease of configuration 
9. Introduction of new libraries
   --> E.g. lodash, css-modules

There are in addition to this, tasks that need to be run: 
1. Templating
2. Linting
3. Testing
  a. Mocha, Chai, Sinon, Jasmine, Jest. 
  b. Pre-Commit
  c. PhantomJS
4. Server

In addition, there are popular libraries and pre-processors that should be taken into consideration: 

1. Sass 
  a. Css-modules/CSSX
  b. Auto-prefixer
2. Trans-compilation
  a. Babel 
  b. Es7 
  c. Typescript 
3. Utility libraries 
  a. Lo-dash
  b. Underscore
4. BrowserSync

I am always looking to update this list, and/or refine it. Comments are always welcome :)